There is an increasing need to reduce domestic demand for potable water, and at the same time to reduce the volume of waste discharged to sewers. Domestic use of potable water generates a substantial quantity of grey water from sanitary ware that includes baths, basins and sinks. Grey water can be recycled and used for other purposes where potable water is not necessary, for example in watering a garden, and in flushing a toilet and in appropriate cycles of clothes and dish washing machines.
A known way of collecting grey water is to direct all the water generated by sanitary ware to a storage tank. For example, the grey water is collected in an external water butt with an over-flow to a drain and an outlet to a garden hose; or the water can be collected in a buried, or a raised, tank, both of which require the use of a pump. In a buried tank the pump would move the water out of the tank when the water is needed; and in a raised tank the pump would transfer the water into the tank for storage.
These systems collect grey water containing various quantities of pollutant. Consequently, the storage tank will collect polluting refuse, and there is a risk of noxious substances being delivered with the grey water. To generate usable grey water the system is fitted with a filter and/or a water treatment unit to clean the water. Furthermore, this type of system is not cost effective to install in a new building or to fit to sanitary ware in existing buildings.
Another known device is used to collect grey water generated by a number of household water appliances. The grey water produced by each appliance has a different concentration of pollutant. The water is directed by a valve in the device to a drainage system or to a recycling system. Therefore, the recycled grey water produced by different appliances is mixed together by the device, limiting the application of the grey water to uses where a certain concentration of pollutant is acceptable. Also, to fit the device to an existing plumbing system, the system needs a considerable amount of alteration because the device is connected to the drainage system at its outflow from the household. Normally the grey water would be directed immediately to a foul water drainage system.
As mentioned, with such prior art grey water systems it is known to provide a valve within the drainage system, which is able to switch water drained from an appliance or item of sanitary ware into either the grey water storage tank, or directly into the drainage system. An example of such a prior art valve is that shown in U.S. Pat. No. 5,313,677. Here, a valve is provided with a first inlet for accepting water from the drain of a bath tub, a second inlet for accepting water from the overflow drain of a bathtub, a first outlet leading to the sewer line, and a second outlet leading to the grey water storage tank. The valve operates to block either the first inlet, the first outlet, or the second outlet only, and all other parts remain open. The valve is arranged to be built into the pipes of the plumbing system leading from the appliance, and a complicated lever system is provided to allow remote operation of the valve. The installation of such a valve requires much modification of the existing plumbing system within a house, requiring access to pipes which may be hidden within walls and the like.
A similar example is shown in FR 2830552. Again, this document describes a valve provided in the outlet pipe from an item of sanitary ware such as a water basin or sink. Again, to install such a valve the plumbing system at the house must be modified, and a complicated pulley system is employed to allow remote operation of the valve by a user standing at or within the item of sanitary ware. With both of these prior art documents, therefore, the remote location of the valves within the plumbing system, rather than at the item of sanitary ware, leads to increased complexity.
It is, however, known to provide switching between directing grey water to a grey water recycling system or the drain, without requiring modification of the plumbing system itself and remote manipulation of any such installed valve. In particular, DE 19613631 A describes a waste for an item of sanitary ware, which appears to provide for switching between supplying the grey water to the drainage system, or a recycling system. However, such a waste is intended for use with a shower, and does not, therefore, also provide for blocking of the outlet, as would be required by a waste for use in a bath or a sink.